This invention relates to a fuel injection system for an internal combustion engine, and more particularly, to an integrated carrier having a fuel injector assembly, fuel rail, wiring harness and connector which may be assembled to a motor vehicle intake manifold.
An air intake manifold distributes air to cylinders of an internal combustion engine. The manifold is typically mounted to a cylinder head of the engine. The manifold is in close proximity to various electrical components of the engine such as fuel injectors, electric throttle body, throttle position sensors and air and temperature sensors.
A conventional fuel injection system includes a plurality of fuel injectors mounted to an intake manifold. Fuel is supplied to each fuel injector through a fuel rail. Each fuel injector is selectively actuated to meter a desired amount of fuel into a combustion chamber. Electric signals for controlling the fuel injectors are typically communicated through a conventional wire harness. Such harnesses include a main connector that is attached to a controller and a plurality of wires that are routed to individual fuel injectors. Conventional wire harnesses are expensive to manufacture and assemble onto the vehicle engine. In addition, wire harnesses are bulky and subject to damage due to the hostile environment that exists within the vehicle engine compartment.
Conventional fuel injection systems include many components that must be assembled, which increases the likelihood of fuel permeating or leaking from the system. The fuel injectors may include an O-ring or other seal at opposing ends that are received in the fuel rail and intake manifold. For a six-cylinder engine, up to twelve seals may be needed solely for the fuel injectors.
Currently, there are very strict rules limiting the amount of hydrocarbons that may leak or permeate from a vehicle. Each connection between components presents a potential for leaking or permeation of fuel vapor. Furthermore, fuel injection systems are under relatively high pressures. As a result, there is an increased opportunity for fuel to leak or permeate past the seals. Accordingly, it is desirable to provide an integrated assembly that reduces the number of connections that must be sealed and that incorporates several different functions such as sealing, electrical connectivity, and fuel delivery to provide for improved sealing and wiring protection along with decreased cost and assembly time.